Since the beginning of 90s, the advent of mammalian gene engineering technology brought the mouse into a central role for investigations of the mammalian central nervous systems. This led to our renewed interest in mouse brain anatomy. As anatomical guidance, mouse brain atlases have been a crucial resource in various aspects of neuroscience studies. These include anatomical references to detect abnormalities, identification of coordinates of specific structures for stereotaxic operations, and templates for registering and reporting locations of histology-based results. The overall goal of this project is to develop and provide MRI-based atlases of developing mouse brains. Most of the currently available atlases are based on digitized histology slices. While they can provide detailed views of brain anatomy, the accuracy of the stereotaxic coordinates could be compromised by distortions related to fixation and sectioning processes. The slice orientations and locations are limited and for stereotaxic operations, the 2D nature of the histology-based atlases is often a severe limitation. In the past grant period, we enhanced our diffusion tensor microimaging technology (Aim 2), established normal brain development database (Aim 1), performed histology-MRI comparison (Aim 3), and developed quantitative analysis tools (Aim 4). We will use these database, technology, and experiences as core resources to propose the renewal of this grant. For the next 5 years, we set the following three aims;Aim 1: To establish atlases of developing mouse brains with full segmentation and annotation Aim 2: To develop image-guided stereotaxic operation of developing mouse brains Aim 3: To provide tools for atlas-based automated anatomical analyses for abnormal brain growth Aim 4: To disseminate the atlases, image-registration tools, and use interface software PUBLIC HEALTH RELEVANCE: In this project, we will develop brain atlases of developing mouse brains. Unlike existing histology- based 2D atlases, our atlases will be based on three-dimensional MRI data. The atlases will provide greater accuracy for stereotaxic operations such as delivery of drags to a specific coordinates in the brain. The atlas will also allows us to perform automated segmentation of the brain after MRI studies of various types of mouse disease models. We believe that these atlases will be important resources for a wide range of neuroscience researches.